Photomixing can involve pumping a high-speed photoconductor that is integrated with a radiating element with two frequency-offset pump lasers. Typically, the beams from the pump lasers are mixed together and focused onto a photomixer device (i.e. photoconductive source and/or detector) which generates the terahertz radiation. The frequency offset of the two pump lasers and, thus, the frequency of generated photocurrent and radiation, can be set to a desired frequency. Technological breakthroughs in fiber optic communications and the availability of high power, widely tunable, narrow linewidth and compact fiber lasers and amplifiers have made telecommunication wavelengths a useful wavelength for pumping photomixers.